Friday, September 18, 2009

It's been an interesting couple of weeks for people interested in handaxes. On one hand, there was the discovery of honking big handaxes in the Lake Makgadikgadi Basin (Botswana), which is currently dry. On the other, there was the report that the age for the oldest handaxes in Europe needs to be pushed back by as much as 300,000 years, based on new chronological and paleomagnetic information (Scott and Gibert 2009). In a way, these two discoveries are related more intimately than might seem to be the case.

First, the new ages for the Spanish handaxes have several implications, some of which are aptly discussed by John Hawks. The first is that how refined some handaxes are is not necessarily a good indicator of their overall age. That is, biface morphology doesn't simply gradually go from coarse to fine over time, and biface morphology is influenced by many factors and essentially reflect use considerations at the end of an individual handaxe's use-life (McPherron 2000). This was a well-established fact before this new study, but these dates underscore that lack of correlation especially well. A second implication is that the Acheulean (yup, that's how you spell it!) is therefore likely to be much older than previously assumed. The general consensus has been for some years that this industry first appeared in Europe around 600kya (cf. Monnier 2006). The age of 900kya for an Acheulean assemblage in Spain thus pushes back that date of first appearance by several hundred thousand years.

What is more, unless you accept that hominins using Acheulean tools came to Spain directly from Africa (across the Strait of Gibraltar?), this age implies that the Acheulean in more eastern parts of Europe must be even older, though hard evidence of this is currently lacking. The earliest Acheulean site outside of Africa is 'Ubediya, in the Jordan Valley, dating to ca. 1.4mya. Assuming a single origin for Acheulean technology, this would mean that the amount of time it took handaxes to diffuse across the European mainland is effectively cut almost in half and now stands at a maximum of about 500,000 years, a long time to be sure, but much less than the previously accepted almost million year interval. This has some important implications in constraining models of early hominin dispersion in Europe and how that relates to the subsequent development of Neanderthals (e.g., Hublin 2009).

And this would make sense, really, given the usefulness of handaxes as a technological innovation. The thing about handaxes is that they are generally described as unchanging over their 1.6my history, although this impression is based on morphology alone and doesn't really reflect the state of thinking among most scholars involved in Lower Paleolithic research. In a nutshell, handaxes were highly polyvalent from a functional perspective and not putting individual occurrences in proper context is what results in this mistaken impression of stasis (Machin 2009, Nowell and Chang 2009). A contextualized approach to handaxe variability is what allows archaeologists to seize on the richness and diversity of Acheulean behavior (Hosfield 2008). It is also what allows us to make sense of outliers like the Lake Makgadikgadi specimens.

By any standard, at 30+cm in length these things are frikkin' huge! Strikingly, the press release only mentions that these very large items were found, without any discussion of how their size is unusual and what this distinctiveness might mean. These specific artifacts are of uncertain age, and their function is also uncertain - at that size, it is unclear exactly what practical function they might have served, as they would have been rather unwieldy to use, unless they were somehow hafted, in which case their heft might be an indication of their ultimate function. Most people tend to assume handaxes were made and used as stand-alone hand-held tools. This lithic-centric view has led to some conjecture that the skill manifest in handaxe manufacture might have served as a form of 'advertisement' to potential mates by especially technically proficient knappers (e.g., Kohn and Mithen 2009). This has been challenged on both theoretical and practical grounds, most eloquently by Nowell and Chang (2008) who detail how such a model cannot, in fact, be argued to be founded on evolutionary theory as commonly defined.

Machin (2009:35-36) argues persuasively that handaxes morphology cannot be understood by reference to single-cause explanations since "variability is caused by the differing motivations and constraints – ecological, physiological, biological, cognitive and social – which act upon the individual agent at any given point in time." The sheer timespan and geographical distribution of handaxes certainly agrees with her - it's unlikely that handaxes served the same function in all contexts in which they are found. In a way, handaxes are perhaps best understood as an especially useful and versatile technological innovation that allowed them to be if not all things to all (pre-)people at least many things to many (pre-)people.

Getting back to the Spanish handaxes described by Scott and Gibert, this raises some interesting questions. The first among these is why, given their recognized usefulness, such implements would be so scarce when they are first documented in the record - at Estrecho del Quípar (the site dating to 900kya), there is only one handaxe in the assemblage, and based on its morphology (Fig. S4: flake scars are present on both sides of the piece, but is not very extensive at all toward the center of either face) some analysts might consider it a core or bifacially flaked cobble instead of a proper handaxe. To be fair, the authors refer to other studies that show that handaxes are not very frequent in most Acheulean assemblages (i.e., Monnier 2006), and they also describe a contemporary Spanish assemblage that lacks handaxes altogether to explain why and absence or low frequency of bifaces is not necessarily a problem to labeling the assemblage as Acheulean. However, this begs the question of what an Acheulean assemblage actually is if not one that contains handaxes, a question that Gilliane Monnier has addressed in great detail, concluding that

It is time for a comprehensive revision of the Lower/Middle Paleolithic periodization based upon a synthesis of multiple aspects of the archaeological record, including climate, subsistence, landscape use, mobility and exchange, symbol use, cognition, and biological evolution, in order to determine whether we should maintain a two-phase system [Lower vs. Middle Paleolithic] and, if so, how it should be defined. (Monnier 2006: 729)

If that's the case, what can we really say about the oldest appearance of the Acheulean without an in-depth consideration of these complementary - and necessary - lines of evidence instead of only focusing on the presence of large bifacial artifacts?

References:

Hosfield, R. Stability or Flexibility? Handaxes and Hominins in the Lower Paleolithic. In Time and Change: Archaeological and Anthropological Perspectives on the Long-Term in Hunter-Gatherer Societies (D. Papagianni, R. Layton and H. Maschner, eds.), pp. 15-36. Oxbow Books, Oxford.

15 comments:

mh. there are many examples of unrealistically elaborate or huge flintknapping, not uncommonly related to burial's or features in the direct surrounding, as such deposited. (the inca's took it farthest i think).

it is almost beyond doubt where they often come hoarded, they were made as a passtime, mark of craftmanship, sheer beauty and sometimes value. after all u wud use an excellent piece of stone that represnted usefull material. with the dedication to craftmanship, and the central function carrying some stone(or actually not carrying it(eg. oetzi but has been researched before)their effectual status is set.

(un)surprisingly they are suggestively dedicated as some sort of sacrifice or afterdeath gift usually. however, the ones more closely associated to humans tend to have usefull proportions,(probably so that they could be 'worn'.) the more outrageous examples could often be a dedicated produce yet it could also be more like a hobby also essential to develop *the*(a) skill necesarry for survival,

still the most extravagant examples would have more of a mystical then monetary value, since to make them or to make them with a higher degree of attention or sophistication implies there is a lot of material for practice about. what follows is that these are rather old, the biggest but one could otherways be more precise, and the resolution of the flaking also suggests a rather limited nr of strikes was perceived best. possibly because of the risk to damage the core. singly that they turned up suggests a catastrophical horizon,(a boat or a shallow remnant)unless they were in a dig in wich case stratification hadn't been so much of a void i think. my impression is that to create singly bigger tools as an expression of craftmanship is more of an older trend, later more of the accent appears on refinement. in both cases they tend to come in close association to another or sites. like i said there are quite a few suggestive 'offerings' including(i think) purposedly broken tools, of a much later date.

What is more, unless you accept that hominins using Acheulean tools came to Spain directly from Africa (across the Strait of Gibraltar?)...

I do. AFAIK the evidence points to two waves of early Homo sp. into Iberia: first, in the south (claimed to have been a Gibraltar crossing) and only much later in the NE (from mainland Europe and ultimately West Asia). This was reasonably true for "Olduwayan" (choppers) industry but now seems to be also the case for Acheulean, as they would have arrived to Iberia about the same time.

At that time, some 900,000 years ago, Gibraltar Strait was much narrower than now and probably had several intermediate islands that could have been used for the journey. The question is: could H. erectus (ergaster, habilis, whatever) furnish some sort of rafts for that purpose. IMO, there's nothing that could impede that: even today Gibraltar Strait can be crossed in good weather by a healthy swimmer with the help of a surfboard in some six hours (the main risk being the heavy ships that transit it all the time), so why could it not be crossed when it was just a third of its current size by a rather smart hominin whose brain capacity was much closer to ours than to chimpanzees?

Anne: hehe - but the size of the handaxes doesn't necessarily imply they weren't used for rather prosaic ends, as I mentioned in the post. It'd take some usewear studies to demonstrate this, but since these appear to have been recovered on the surface, it's unlikely this would be a very useful thing to do.

Onix: there is no reported contextual information about these handaxes, which makes it difficult to assess how they might serve a social or communication function. Nowell and Chang (2008) and Machin (2009) talk about this is great depth in their paper, and about how risky it can be to infer potential symbolic function from such artifacts by reference to our perception of them.

Archaezoo: it's not the size of the handaxe, it's how you use it!

Maju: from my perspective, this isn't impossible, but it would need to be demonstrated somehow, rather than assumed as likely. Lawrence Straus had a very good paper about this very issue in 2001 in Quaternary International ("Africa and Iberia in the Pleistocene"), and if I remember correctly he concluded that the only unambiguous evidence for cross-Strait contact comes in the Late Upper Paleolithic.

In the late Upper Paleolithic? I am unaware of those. I'm just an amateur but for what I've read in various books (universitarian or divulgation) and online papers, there are two moments that seem to imply crossing the strait before Neolithic:

1. The arrival of the first hominins, which is first and more frequently documented in Southern Iberia not far from Gibraltar (El Aculadero, etc.). Early Acheulean itself is also better documented in the south of the peninsula (southern Portugal and some sites in the Tajo valley - and now also these particularly old Andalusian sites).

2. The other would refer to the relations between Gravetto-Solutrean and Oranian (Iberomaurusian) already in the middle Upper Paleolithic (rather than the late one). You may be refering to this one, though it's also a controversial issue because a lot of prehistorians insist now in Oranian being original from the Nile area (what I disagree with based on datations, older in the west, and genetics: NA mtDNA is partly a subset of Iberian one) what would totally dilute any meaning for these trans-Gribaltarian contacts.

Well, it did seem to me that these handaxes were awfully large! Still, they could have been used as digging tools, maybe they were real choppers! But Onix has a point. I've seen examples of some Clovis points, some of which seemed to this inexpert person to again be rather large for their supposed intended use. But I don't pretend I'm an archaeologist, so I'll leave the arguments for and against their practicality up to those who know more about this than I do.

Maju -well, the key word here is "imply" - there's certainly suggestive evidence, but no unambiguous empirical proof of these transfers. If you add to that the fact that Neanderthals seem to have persisted in southern Iberia longer than anywehre else in Eurasia and with no apparent contact with North Africa, it seems that, for whatever reason, the Strait might have served as a biogeographic barrier for humans for most of the Pleistocene.

Anne: well, they are very large. But on current evidence, we have no way of knowing what they were used for, if anything. Certainly, a social function is a possibility but this need to be demonstrated. As for the Clovis reference, you're right that some of points may have been too overdesigned to be functional knives or spearheads - that said, it can be risky to extrapolate from Clovis to the Acheulean, given the behavioral differences between the species responsible for both industries and the lower investment required to produce a fine handaxe than a fine Paleoindian point. In any case, many caches of Paleoindian points include implements that were used to hunt/process large animals in spite of their striking appearance. The discovery of the Mahaffy cache in Boulder, CO last year is a case in point.

Of course you're right. I didn't think I was exactly "extrapolation" from Clovis to the earlier Pleistocene, though. I was just pointing out that these Clovis points I was referring to, don't seem to have been anything but nonfunctional. And maybe that was the case for those handaxes, too. Or maybe not. Unfortunately, the people who made the handaxes aren't around to explain what, if anything, they were used for. Which is often a problem in archaeological contexts!Anne G

I didn't think I was "extrapolating" from those Clovis points I was referring to, so much as pointing out that some archaeological artifacts at least appear to be nonfunctional. Of course it's risky to extrapolatie from one archaeological context to another. And you're right. Unfortunately, the people who made the big handaxes aren't around to tell us what they were used for. Whcih, of course, is often a problem in archaeologcial contexts.Anne G

There are people who have interpreted any handaxes as "really" being cores. This ia handaxes of any size, not just big ones. They are basically saying that flaking was a technique used farther back than we generally think of flaked tools being made. I can't remember the name of one of the people who thought of this, but Julien probably knows.Anne G